She’s still not out to her parents

So, I’ve been dating my gf for about 2 years now. And she’s still not out to her parents . She’s out to basically everyone else in her family except them. I feel like it puts such a “pause” on our relationship. Like we truly can’t move forward . Anytime I bring it up she kinda just gets nervous and says she will do it soon but never does. I understand being scared to come out etc but how long is too long ? Advice ?